1. Field of the Invention
The invention relates to a lock structure of a spherical bearing and more particularly, to the lock structure of a spherical bearing for restraining an outer race from turning relative to a housing.
2. Description of Related Art
Conventionally a spherical bearing in which a spherical surface of an inner race is slidably supported on an inner spherical surface of an outer race has been well known. Such a spherical bearing has been widely employed for a rod end of a link member and the like. FIG. 6 shows an example of a lock structure of a spherical bearing 11. In this lock structure, the spherical bearing 11 is locked to a housing 14 through staking (also referred to as V-staking) for locking an outer race 12 to the housing 14 by staking a V-shaped groove 13 as an annular staking groove formed in each side of the outer race 12 using a dedicated tool (not shown). This makes it possible to easily lock the spherical bearing 11, and be widely used for various applications.
In a case of an eccentric spherical bearing 21, a large rotatiing torque is exerted to the bearing. In the state where the bearing is locked only through staking, the outer race 12 may turn relative to the housing 14, which may cause the risk of wearing an outer peripheral surface 12a of the outer race 12. It is, thus, necessary to restrain the turn of the outer race 12 relative to the housing 14. In order to solve the above-described problem, referring to FIGS. 7 and 8, a flange 26 is formed on the edge of one side of an outer race 25 and an extending portion 26a is formed by extending a part of the lateral edge of the flange 26 in a radial direction of the outer race 25. Additionally a screw portion 24 is formed on the outer peripheral surface of the other side of the outer race 25. Then the outer race 25 is inserted into a bearing hole 23 to bring the flange 26 into abutment against a housing 22, a lock nut 28 is screwed to be locked to the screw portion 24 of the outer race 25 through a lock washer 27, and a pin 29 is driven into the housing 22 to penetrate through the extending portion 26a of the flange 26. As a result, the spherical bearing 21 is locked to the housing 22 while restraining the outer race 25 from turning relative to the housing 22. The above-identified lock structure for the spherical bearing 21 has been conventionally employed.
The lock structure of the spherical bearing 21 described above requires additional parts for locking the spherical bearing 21 to the housing 22, that is, the lock washer 27, the lock nut 28 and the pin 29, resulting in complicated component control as well as in deteriorated efficiency of assembly. Moreover, the flange 26 of the outer race 25 has to be extended to drive the pin 29, causing increase in the material cost owing to increased size (weight) thereof.
In view of the foregoing problem, it is an object of the invention to provide a lock structure of a spherical bearing having a simple structure, which is capable of restraining an outer race from turning relative to a housing to simplify the assembly and to reduce the cost, and the lock method thereof.
In order to achieve the above objects, according to a first aspect of the invention, the lock structure of the spherical bearing having a spherical surface of an inner race slidably supported on an inner spherical surface of the outer race which is fitted into a bearing hole of the housing so as to be locked thereto includes a protruding portion formed on a periphery of one side of the bearing hole, a flange formed on one side of the outer race, an engagement portion formed in the flange to be brought into engagement with the protruding portion, and an annular staking groove formed in the other side of the outer race.
With the aforementioned structure, the spherical bearing is fitted into the bearing hole to bring the engagement portion formed in the flange of the outer race into engagement with the protruding portion on the periphery of one side of the bearing hole. Meanwhile the staking groove in the other side of the outer race is staked to lock the spherical bearing to the housing.
In order to achieve the above objects, according to a second aspect of the invention, a method of locking the spherical bearing having the spherical surface of the inner race slidably supported on the inner spherical surface of the outer race which is fitted into the bearing hole of the housing so as to be locked thereto includes the protruding portion formed on a periphery of one side of the bearing hole, the flange formed on one side of the outer race, the engagement portion formed in the flange to be brought into engagement with the protruding portion, and the annular staking groove formed in the other side of the outer race, in which the engagement portion is brought into engagement with the protruding portion and the staking groove is staked so as to restrain the spherical bearing from turning relative to the housing.
With the aforementioned method, the spherical bearing is fitted into the bearing hole to bring the engagement portion formed in the flange of the outer race into engagement with the protruding portion on the periphery of one side of the bearing hole. Meanwhile the staking groove in the other side of the outer race is staked to lock the spherical bearing to the housing by restraining the spherical bearing from turning relative to the housing.